Device for the detection of electromagnetic waves and, in particular, of infrared radiation

Abstract

A device is provided for the detection of infrared radiation which operates at low temperature. The device contains a detection unit and a cryostat equipped with a cold finger to exchange heat with a cold source. Included is a cold plane having at least one machined portion, each portion having a recess toward the center of the cold plane in the region of a through-slot opening outside the cold finger. A connection element is positioned by insertion into each recess, and is electrically connected to the connector of the cryostat.

I claim: 
     
       1. A device for the detection of infrared radiation, which operates at low temperature and comprises: a cryostat equipped with a cold finger (1) intended to exchange heat with a cold source;   a cold plane (2) arranged generally perpendicularly relative to the cold finger (1) and mechanically fixed to and in heat exchange with the latter;   a detection unit comprising at least one detection circuit proper (4), sensitive to the infrared radiation to be detected, and a read and analysis circuit (3) electrically connected to the detection circuit (4), said detection unit being fixed mechanically and thermally on a connection circuit (7), itself secured to the cold plane, said connection circuit (7) conducting heat between said cold plane (2) and the detection unit (3, 4) and being additionally intended to transfer the electrical signals output by the detection unit (3, 4) to the internal connection system of the cryostat at a connector (8, 19) which passes the electrical conductors out of the cryostat in leaktight fashion,   wherein the cold plane (2) is provided with at least one machined portion, each of said portions consisting of a recess (16) extending between one of its peripheral edges toward the center of said cold plane (2) in the region of a through-slot (15) opening outside the cold finger (1) when the cold plane (2) is in place at the end of the latter, and wherein each of said recesses (16) accommodates a first connection element (13) positioned by insertion into this recess and fixed by bonding, each of said first connection elements (13) being electrically connected to the connector (8, 19) of the cryostat by means of second connection elements (14) passing through said through-slot (15), said first connection element (13) being electrically connected to the connection circuit (7) at the peripheral free end of said first connection element (13).   
     
     
       2. The device for the detection of infrared radiation, as claimed in claim 1, wherein the first connection elements (13) consist of ceramics including metallized conductive tracks (18) extending parallel over their entire length, and therefore radially relative to the center of the cold plane. 
     
     
       3. The device for the detection of infrared radiation, as claimed in one of claims 1 and 2, wherein the depth of the recesses (16) is greater than the thickness of the first connection elements (13).